Trump has a corporate tax plan. Economists have some questions.

President Trump holds the state flag of Texas outside of the Annaville Fire Department after attending a briefing on Hurricane Harvey in Corpus Christi, Tex., on Tuesday. (Jim Watson/Agence France-Presse/Getty Images

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President Trump's much-awaited speech about his plans for tax reform has fired up the debate about who really wins when taxes are slashed.

The president has previously proposed cutting the corporate tax rate from 35 percent to 15 percent — a move budget experts project would cost the country $2.4 trillion over a decade. The reduction, he has argued, would encourage companies to stay and grow and hire in the United States.

“We need a competitive tax code that creates more jobs and higher wages for Americans," Trump said Wednesday in Missouri. "It’s time to give American workers the pay raise that they’ve been looking for for many, many years."

Treasury Secretary Steven Mnuchin has also said job growth is the primary goal of tax reform. “We want to make sure that companies bring back that money onshore to reinvest in American equipment and American jobs,” he told CNBC in a June interview.

Economists have long clashed over whether tax cuts lead to jobs growth. Businesses tend to be chiefly motivated by profit, and there’s no guarantee the cash they keep from Uncle Sam would go toward hiring people on American soil. But some argue lowering the country's corporate tax rate, among the world’s highest, would encourage companies to come here, and stay here, and so generate more employment.

A new report from the Institute for Policy Studies, a progressive think tank in the District, comes down solidly against that argument, asserting companiesthat reap more tax savings aren't more likely to expand their workforce.

Since the tax code is full of loopholes, most firms already pay less than 35 percent — the average effective rate for big, profitable businesses was 22 percent between 2007 and 2011, according to the Treasury Department’s latest calculations.

Ninety-two companies fit that description, including AT&T and General Electric, according to the report. The group’s median job growth over the seven-year period was negative 1 percent, the authors determined, compared with 6 percent among all private firms.

The researchers also pointed out that 48 of the 92 companies got rid of jobs between 2008 and 2016, a period that includes the recession, shrinking by a combined 483,000 positions.

These firms gave their top brass bigger raises, too, the data show. The average chief executive pay among the 92 companies increased 18 percent from 2008 to 2016, while S&P 500 chief executives saw a 13 percent boost. (IPS looked at employment data from 2016, the latest numbers available, with 2015 ITEP analysis.)

In contrast, workers across the private sector saw a 4 percent bump over that period, the authors calculated.

Sarah Anderson, the global economy project director at IPS, said she wants to see Trump focusing on closing tax loopholes, rather than reducing the corporate rate.

“How can they claim that they’re going to turn tax savings into job creation when they've already been getting hugely reduced tax bills and they’ve been cutting jobs?” she said.

One company Anderson highlights in the report was GE, which, according to the ITEP numbers, paid no federal income taxes between 2008 and 2015 and also reduced its workforce over that time by about 14,700.

GE spokeswoman Tara DiJulio said the report “recycles misinformation” and overlooks $6.2 billion the company paid in 2015. The smaller workforce, she added, reflected GE’s decision to sell NBCUniversal to Comcast, among other deals.

“The tax code is complex and outdated, which is exactly why tax reform must happen this year,” she said. “GE has long been advocating to simplify and modernize the tax system — even if it means we pay more in taxes.”

In response to IPS’s findings, an AT&T representative said the company pays “billions” of dollars in taxes each year and invested $135 billion back into the United States over the past five years.

Eric Toder, co-director of the nonpartisan Tax Policy Center, said giving companies a break shouldn’t be framed as a jobs initiative. Unemployment is already sitting at a 16-year low (4.3 percent). The more plausible win, Toder said, would be a raise for the workforce.

“If a corporate tax cut attracts investment, it's going to help workers in the sense that wage growth will be somewhat bigger,” he said.

The drawback, he added, is that Trump has yet to propose a specific way to pay for the tax relief, with his advisers saying the economic growth would make up for any losses. Businesses are expected to hand over $340 billion in corporate taxes next year, or about 10 percent of all revenue absorbed by the government.